Reservoir for congealable liquids



Patented Sept. 21, 1954 Harry T. Booth, Dayton, Aircraft Products, Inc

raton of Ohio Ohio, assignor to United Dayton, Ohio, a corpo- Application August 17, 1951, Serial No. 242334 8`Claims. l

This invention relates to systems circulating a congealable liquid, and particularly to a reservoir for use therein.

While not so limited, the invention has particular reference to storage tanks used in the lubricant circulating systems of aircraft. such tanks customarily include an inner hopper providing for a segregated flow of lubricant, as during the periods when a diluent is added to the system and during the warm up period of engine operation. Valve means, responsive to a changing condition of the lubricant, and possibly to other influences, is operable to Shift the flow of oil returning from the engine from the hopper to the main portion of the tank and back again.

Advantage is taken of the location of the hopper in the tank to transfer some of the heat of the oil passing through the hopper during the warm up period to the oil standing in the tank. This is desirable in cold weather operation because the standing o'l in the tank may be congealed or highly viscous. When the automatic valve controls Shift flow from the hopper to the tank, it is necessary that the oil in the tank be fluid and flowable, or at least that a relatively large path through the tank be opened, else the Volume of oil supplied the engine may be critically reduced.

In tank constructions as heretofore known, warming and decongealing of the oil in the tank by heat transfer through the wall of the hopper has been accomplished. Particularly under severe weather conditions, however, the process is a relatively slow one, requiring prolonged warm up before a suitable path is opened through the tank. The instant invention contemplates a more rapid conditioning of the oil in the engine, it being proposed to make more efficient use of available heat and to conduct such heat farther and more directly into the main body of oil in the tank. In this connection there is presented a novel finned construction for the hopper wherein the heat transfer action gained by the fins is separate from or additive with respect to conducton through the Wall of the hopper.

The invention further has special reference to tank structure in which a conduit in the tank is used in the delivery of oil to the tank, it being proposed to mount the conduit in such relat'onship to the finned hopper as to promote the maintaining of an open passage therethrough, in conjunction with and sequential to the establishing of a fluid condition around t e conduit.

Other objects and structural details of the invention will appearfrom the following description when read in connection with th e accompanying drawing, wherein:

Fig. 1 is a partly diagrammatic view of an oil tank or reservoir in accordance with an illustrative embodiment of the invention; and

Fig. 2 is a View in top plan in which the location of the stand pipe inlet conduits are shown more nearly in an actual location rather than diagrammatically, as in Fig. 1.

Referring to the drawings, a reservoir in accordance with the illustrative embodiment of the invention comprises a tank ll, here indicated in a diagrammatic form, closed by a lid !2. i A hopper |3 is suitably disposed in the tank ll for segregated flow therethrough, the lower end of the hopper having a necked portion I4 received in an opening !5 through which liquid in the hopper may discharge through the i bottom of the tank.

With the hopper !3 Also in the bottom of the tank are inlet openings [6 and ll for delivering liquid respectively to the tank and to the hopper. Installed in opening 16 is a stand pipe |8 which extends upward in parallel adjacent relation to the hopper |3 to a point above the normal liquid level in the tank, as indicated by a line !9. The opening ll receives a stand pipe 2| which extends up'ward in similar manner in the tank and into a chamber 22 defined by an overfllow and foam tray 23. The tray 23 is supported by or made an integratedpart of the hopper l3 and presents a large central opening 24 registering and from which the tray extends in slightly inclined relation. Accordingly, liquid which enters the reservoir by way of opening I'I is conducted by pipe 2l to the chamber 22 from whence it flows into the top of the hopper [3. Passing downwardly through the hopper, such liquid is discharged from the reservoir by way of opening l5. Similarly, liquid admitted to the reservoir by way of opening s is conducted by way of pipe 18 to the upper region of the tank where it is discharged above the liquid level IS. Flow out of the tank is permitted through a suitable opening in the bottom thereof, as for example through the annular opening 25.

Referring to the hopper !3 in more particularity, it is in the illustrated instance a fabricated assembly comprising a radial series of flat sheet metal elongated members 26 and interconnecting segments 21. The segments 21 are aligned with one another in a circular formation, with the adjoining ends of adjacent segments in abutting relation to a member 26, intermediate the side edges of such member and on opposite sides thereof. By means of welding, rivetng or the like the members 25 and segments 21 are joined into a unitary structure with the segments Zi cooperating to define the wall of the hopper and with the members' 26' defining heat transfer fins. As indicated the inner edges of such fins lie adjacent to the axis of the hopper, large areas thereof being accordingly washed by the liquid' descending through the hopper.

Extending in effect through the wall of the hopper, the fins 26 project 'radially outward into the main body of liquid in thetank ll. Assumng the liquid fiowing through the hopper !3 to be hot and fluid and the liqu'd in tank H to be cold and viscous, it will be apparent that the fins '26 provide for rapid and eicient heattransfer from the liquid in the tank to a comparatively large 'body of liquid in the tank to the end that the iiqud in the tank may be more readily conditioned for flow.

The location of the tank inlet Conduit 18 in parallel adjacent relation to the hopper 13 contributes to the maintaining of a'ireely open path through this pipe. 'such effect is aided by the fins 26, adjacent ones of which define a pocket receiving the pipe iii, as well as the pipe 2-1.

Itwill be understood, however, that it is ordinarily desirable that the thawing out of congealed oil in the pipe 48 be made dependent upon and subsequent to the eonditioning of the oil in the tank around the pipe. Itis of course undesirable to discharge oil into the tank untila path therethrough to the outlet is opened. Some form of restrictve means responsive to a changing condition of the oil may be used in the pipe s, in this connection, to delay the opening of the flow therethrough. The conduits i& and ZI may be supported by the hopper, as through brackets 28 and 29, seen in Fig. 2.

What is claimed is:

1. A reservoir for use in a system circulating a congealable liquid comprising a tank, a hopper in said tank providing for segregated flow through the tank, a series of heat transfer fins projecting radially from said hopper and extending longitudinally thereof and inlet conduits for admitting liquid to said tank and to said hopper extending in adjacent parallel relation to said r hopper substantially throughout the length thereof in pockets formed by adjacent fins on said hopper.

2. A reservoir for use in a system circulating a congealable liquid, comprising a tank, a hopper in said tank providing for -segregated flow through the tank, a series of heat transfer fins projecting radially from said hopper and extending longitudinally thereof, and separate inlet conduits for admitting liquid to said tank and to said hopper, the inlet Conduit to 'said tank having the form of a stand p-ipe which is in adjacent parallel relation to said hopper substantially throughout the .length thereo in a pocket formed by adjacentfins on said hopper.

3.' A reservoir for use in a` system circulating a congealable liquid, comprising a tank, a hopper in said tank providing for segregated flow through the tank, outlet meansopening through the bottom of the tank from' said tank and hopper, separate inlet openings in the bottom of said tank to said tankand to said hopper, and stand pipes communicating 'with respective inlet 4 openings and extending to points normally above the liquid level in said tank and hopper, the stand pipe delivering into the tank extending in parallel adjacent relation to said hopper for substantially the full length thereof.

4. A reservoir according to claim 3, characterized by a series of radially outward projecting fins on said hopper extending longitudinally thereof, the said stand pipe delivering into the tank lying in a pocket defined by adjacent fins von said hopper,

5. A storage tank for use in an engine lubricant circulating system, including an outer tank shell i holding the main body of stored lubricant, a

hopper in'said tank shell spaced from the side -walis thereof, through which a part of the lubricant in the system may be circulated in segregated relation to the main body thereof, outlet openings in the tank shell eomrnunicating respectively with one end of said hopper and with the tank area outside the hopper, the latter defined opening being in adjacent relation to said hopper, irlet openings in the tani; shell communicating respectively with the other end of said hoppe' and with the tani; area outside of said hopper, conduit means ior directing fiow entering by Way of .the last defined inlet opening in adjacen't parallel relaton to 'said hopper, and radial fins on said hopper extending longitudinally thereof and projecting out into the main body of lubri- .cant, an adjacent pair of said fins being in embracing relation to said Conduit means.

6. A storage tank according to claim 5 characterized by an overfiow tray fastened to the said other end of said hopper and defining with the tank shell .an overfow 'compartment in communica-ting relation to the inlet opening to the hopper and in -non-communicating relation to the iniet opening to the area outside the hopper.

'7. A reservoir for use in a system circulating a congealable liquid comprising a tank, a hopper wall in said tank -defining a hopper providing for segregated flow through the tank, a series oi radi'ally projecting heat transfer fins on said hopper wall and extending longitudinally thereof, and an ,inlet conduit for admitting liquid to said hopper extending in adjacent parallel relation to said hopper wall substantially throughout the length thereof in pockets formed by adjacent fins on said hopper wall.

8. A reservoir for use in a system circulating a congealable liquid comprising a tank, a hopper wall in said tenk definine a hopper providing for segregated flow through the tank, a series of radially projecting heat transfer fins on said hopper wall and extending longitudinally thereof, and an inlet Conduit for adinitting iiquid to said tank extending in adjacent parallel relation to said hopper wall substantially throughout the length thereof in pockets formed by adjacent fins on said hopper wall.

References Citedin the file of this patent UNITED STATES PATENTS 

